Adjustable pump piston



h. A. MUELLER ADJUSTABLE PUMP PISTON Filed April 7 2O 1925 V R. RAM/aller- Patented Get. 27, 1925.

UNITED STATES ROBERT A. MUELLER, F HOUSTON, TEXAS.

AnJusrAnnn PUMP ris'ronl Application filed April 20, 1925. Serial No. 24,638.

To all whom it may concern:

Be it known that 1, ROBERT A. MUELLER,

a citizen of the United States, residing at Houston, Harris County, Texas, have invented a certain new and useful Improvement in Adjustable Pump Pistons, of which the following is a specification. I

' My invention relates to pump pistons and more particularly to pump pistons usedon horizontal pumps of the double action type, such as are employed in pumping the flushing fluid in well drilling operations.

, It is an object of the invention to provide a pump piston and the cylinder in which it works, so constructed as to allow the packing to be expanded when necessary without removing the piston from the cylinder. It is also desired that the packing be expanded without rotating or mutilating the packing ring. It is a further object to compress the packing longitudinally and expand the same outwardly with a minimum amount of adjustment of the expanding mechanism.

Referring to the drawing, there is shown a central, vertical section through one end of a pump cylinder, with a piston therein showing my invention employed thereon. The pump housing is shown only fragmentarily. There is a cylinder 1, having a lin- 30 ing 2 therein in which the piston 3 is adapted to work. The end of the cylinder housing 1 is extended beyond the cylinder and has a cylinder head 4t secured thereon by means of the cap screws 5 extending through the margin of the cylinder head and the flange 6 of the cylinder housing.

The piston 3 is a solid block, cylindrical in general outline, with a central opening therethrough to receive the piston rod 7. The forward end of the rod is extended some distance beyond the head of the piston and is threaded at 8 to accommodate the packing-expanding device which will be described. The outer end of the piston is recessed to receive a nut 9 by which it is clamped upon the tapered portion 10 of the piston ro The forward end of the piston is reduced in diameter to provide a seat 11 for the packing ring 12 of rubber or other flexible material or composition. Said packing ring may be slightly wider at its inner side than on its outer side to fit beneath a slightly wider-cut shoulder 13 upon the piston head.

The follower plate 14: at the forward end of the piston is formed as a cap fitting overthe reduced end of the piston. lit has a forwardly-extending sleeve 15 thereon which is spaced slightly from the piston rod on its inner surface. It is threaded internally on the forward end to receive an elongated tubular nut 16, threaded on its inner side to screw upon the piston rod 8, and threaded enteriorly in the opposite direction to screw within the sleeve 15. The piston rod is threaded with a righthand or clockwise thread, and the outer surface of the nut has a lefthand or counter-clockwise thread. The forward end of the nut 16 has a polygonal-head 17 thereon to enable it to be operated through a wrench in the usual manner. I also provide a lock-nut 18 on the nut-16 and a locknut 19 upon the piston rod.

To enable the operator to obtain easy access to the adjusting mechanism the cylinder head 4- has a central opening thereinthreaded at 20 and an elongated cap or bull plug 21 is screwed therein. Said bull plug thus serves as a housing for the end of the piston rod and the adjusting mechanism; but may be easily removed when it is desirable to adjust the pressure on the packing ring 12.

The operation of the device becomes nec-- essary when the packing becomes worn so that there is no longer a close fit with the cylinder. The hull plug 21 is then unscrewed and a wrench employed to loosen the lock nuts 18 and 19 after which the nut 17 is rotated in a righthand direction. It is thus moved inwardly along the threaded portion 8 of the piston rod. It also acts to screw the sleeve 15 forwardly "on the nut 16.

This is accomplished because of the lefthand threaded engagement between the tubular nut 16 and said sleeve. In this man ner the follower plate 14 is not rotated, but is moved toward the piston with a double thrust due to the action of the nut 16. If at any time the follower plate tends to rotate when the nut 16 is rotated, a pipe tongs may be employed to hold it from rotation while the nut 16 is being screwed up.

The advantages of this construction lie in the ease and dispatch with which the packing may be expanded, and also in the fact that the follower plate is not rotated but is simply moved strongly against the packing ring to expand it by only a short turn of the nut- 16. When tightened again, the lock nuts may be employed to retain the parts in adjusted position, untiliurtheradjustment may beeo-nienecessaryl p Having thus described my invention, what I claim as new and desire to protect by Letters Patent is: 'l 1 1. In a. pump, a cylinder, a cylinder hea detaohably mounted thereon, a piston-rod-,-a

lower plate on the forward end 01' said pis ton bearing against said packing ring a for: ward sleeve on said plate spaced outside said piston rod extension, and a nut having threaded ei gagcznent with said rod on its inner surface, and also with said sleeve on its outer surface, but in an opposite-direction, whereby the rotation of saidnut will "force said sleeve and plate toward said'pis: ion with a double thrust in the manner described.

23. in a pump, a cylinder, :1 piston therein, a piston rod extending through said piston" tor some distance and threaded," av nut thereon clamping saidpiston immov'ably on said" rod, a packing ring on said piston, a f0l lor-cer plate bearing against said -ring, a sleeve on said plate surrounding said piston rod extension, and an elongated nut on said rod having threaded engagement with said rod and sleeve, but in opposite directions, whereby the rotation of said elongated nut will force said sleeve and plate slidably along said rod.

l. In a pump, a cylinder, apistlori therein,

a piston rod passing through said'piston andv having a forward threaded extension thereon, insane to clamp said piston iirmly' on said rod, a packing ringon said piston, a follower platepand an elongated nut on said, piston rod 1 extension having; ,tlireaded en;

a n. rod having a threaded enga efor said piston rod extension;

on saidrod, a packing ring on said piston, a

follower plate, and. an elongated nut one-said, piston md cxtension having threaded Q'fcri gagement with, both thepi'ston .rod and 01 lower a plate, said, engagement bein operable in opposi-te directions, whereby nut may force and plate jnonrotatablyf along said ii o'd with a double thrust, and removable means to house said piston rod extension and said nuti 6. in" a pump,- a-oylinder, a piston therein,- a m 'st-onjrod passing througl gsaid piston and having a forward threaded eitension there-- on,- means to secure said; piston,- rigidly, on said rjod, a "flexible packingring on said pis ton, a followerplate having a sleeve thereon outside "said rod, and means on saidrpiston rod extension, having threaded'engagement with said'sleeve and said'irod, to move said sleeve and follower. plate non'rotatably .on' said rod against saidpaokingiring. V

7. In a punip'pist'on, a piston head, a piston rod having a forwardthreadedextension projecting beyond said piston head, a pack ing ring of flexible mzfiterial on said piston," a followeiiplateon the forwardend of said piston engaging saidring, a tubular exten= 00 sion on said'plat'e, a nuthaving a right hand threaded engagement withsaiduocl-and a lefthand threaded ."engagement' with 1 said tubular extension, and a removable housing:

8. In'apump piston, "a'head, a packing ring of flexible 'niatelial there'on',; ,a piston. rod, projectingthrough said head and: having a forward extension thereon, means to secure said piston on said rod, la follower: plate bearingagainst jsai-d packing-ring, and ineans'on-the forward end of said rod to hold said plate normally against movementin either direction and adapted to'force it nonrotatably againstsaid ring when desired In testimony whereof I hereunto alibi-my signaturethis 6th day of April, A. 1925', i ROBERT A". MUELLER-f" 

